At present, wide use has been found for pipeline transmission systems for conveying suspensions of solid loose materials in water or other fluid media. Main pipelines are being constructed on a large scale for the transmission in water of minerals at long distances. A number of countries are making use of such systems for transporting coal, ore and other minerals.
Reliable operation of such systems depends largely on the performance of pipeline fittings, particularly gate valves, which are essential for hydraulic pipeline transmission.
Gate valves are even more popular in hydraulic transmission pipelines used in mineral resources treatment factories. These include dressing mills of coal mining and related industries, where concentration processes are carried out in a water medium.
Extensive use of gate valves is associated with hydraulic recovery of fossils, civil engineering and other applications.
Elements of major functional importance in a gate valve are its gate and valve seat. Reliable abutment of the gate to the valve seat is essential to ensure the absence of leaks in the gate valve passage and to extend the service life of these mating parts.
In view of the aforementioned, the provision of gate valves capable of reliably blocking the flow of slurries carrying solid particles is a major problem to be solved in the art.